1. Field of the Invention
The present invention generally relates to marking and inscribing gemstones, particularly diamonds, with indicia identifying the gemstones by heating surface portions of the gemstones upon exposure to radiant energy in a fused marking pattern corresponding to the identifying indicia.
2. Description of the Related Art
Laser etching or inscribing of a diamond surface for the purpose of permanently identifying a diamond is well known. U.S. Pat. Nos. 4,392,476; 4,467,172; 5,753,887; 5,932,119; 6,211,484; 5,149,938; 5,410,125; 5,573,684 and U.S. patent application Ser. No. 09/785,631 filed Feb. 16, 2001 are representative of known laser marking systems that employ lasers, beam delivery and imaging components, gemstone fixtures, servomotors, optical encoders, and programmed computers for controlling the marking procedure.
Such marking systems not only occupy a large volume of space to accommodate all of their various components, but also are costly to purchase and operate. As a result, such systems are typically installed at one or more authorized sites, such as a gemological laboratory or institute. Jewelers and like customers desiring gemstones to be marked send the gemstones to the site of the marking system, and wait for the marked gemstones to be returned.
Many jewelers dislike sending precious items out of their hands and, hence, out of their sight and control, but perhaps, more importantly, dislike having to wait for their return. Yet, the size and cost of laser marking systems dictate against any one jeweler""s purchasing and installing such a system at the jeweler""s premises. Such systems also require skilled, trained personnel to operate the system. This requirement is typically difficult for the average jeweler to meet.
Another U.S. patent application Ser. No. 09/858,846 filed May 16, 2001, etches a diamond by igniting a flammable substance applied in a burn pattern to the diamond. This technique requires close monitoring of the flame produced after ignition to avoid the risk of fire.
One object of this invention is to enable gemstones to be marked with identifying indicia without using large sized, costly laser marking systems or flame etching systems.
Another object of this invention is to reduce the skill level required for personnel to mark gemstones.
Still another object of this invention is to enable gemstone marking on-site at a jeweler""s premises.
Yet another object of this invention is to increase the use of gemstone marking by making the procedure more available and affordable and safer to jewelers.
In keeping with these objects, one feature of this invention resides in a gemstone marking system and method that apply a fusible coating on a surface of a gemstone, for example, on a diamond girdle. The coating may be applied over the entire surface, or only over selected areas of the surface by use of a stencil having cutouts corresponding to identifying indicia for the diamond. A high melting point substance or mixture having a melting point greater than that of the diamond may be used for the coating. The substance or mixture is exposed to a radiant energy source and heated to fuse the coating on the surface in a marking pattern corresponding to the indicia. When the stencil is used, the substance or mixture filling all the cutouts is preferably simultaneously heated. When the stencil is not used, the energy source, preferably a laser, emits a laser beam and directs the laser beam and/or the energy source to move along the marking pattern. The marking can be performed at a jeweler""s premises.
The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.